Manufacturing process for substrate structure having component-disposing area

ABSTRACT

A process for a substrate having a component-disposing area is provided, and includes the following steps. A core layer including a first surface, a metallic layer and a component-disposing area is provided. The metallic layer is disposed on the first surface and patterned to form a patterned metallic layer including pads located in the component-disposing area. A first dielectric layer is formed on the first surface and covers the patterned metallic layer. A laser-resistant metallic pattern is formed on the first dielectric layer and surrounds a projection area of the first dielectric layer. A release film is disposed on the projection area and covers a portion of the laser-resistant metallic pattern within the projection area. A second dielectric layer is formed on the first dielectric layer and covers the release film and the laser-resistant metallic pattern. A first open hole and a plurality of second open holes are formed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional application of and claims the prioritybenefit of U.S. application Ser. No. 13/740,286, filed on Jan. 14, 2013,now allowed, which claims the priority benefit of Taiwan applicationserial no. 101143499, filed on Nov. 21, 2012. The entirety of each ofthe above-mentioned patent applications is hereby incorporated byreference herein and made a part of this specification.

BACKGROUND

1. Field of the Disclosure

The disclosure generally relates to a substrate structure and amanufacturing process thereof, and more particularly, to a substratestructure having a component-disposing area and a manufacturing processthereof.

2. Description of Related Art

In recent years, with ever-changing advances in electronic technology,high-tech electronics industry appeared one after another, which makesthe more humanized and better in function electronic products continueto be launched. And these electronic products are developing toward thelight, thin, short and small figure design. Usually in these electronicproducts, a circuit substrate is disposed for carrying single electroniccomponent or a plurality of electronic components. However, disposingthe electronic components on a circuit substrate will result in anincrease of carrying area, and thus how to make the electroniccomponents hidden in the circuit substrate has become a key technologyin today.

In the prior art, to bury the components in a substrate, it needs toform an open hole in a core layer by laser drilling or mechanicaldrilling, followed by disposing the components in the open hole.However, the components must be electrically connected to the circuitlayer of the circuit substrate through pads, and thus, a solder masklayer must be formed in advance in the process at the position where theopen hole is disposed to facilitate the successive process of pads. Inparticular, the process should be performed separately from otherprocesses of the circuit substrate, which makes the process morecomplicated. Specifically, during the laser drilling for the open hole,the penetrating depth of laser must be controlled very accurately toavoid penetrating the solder mask layer by drilling or having residue ofthe solder mask layer. All the above-mentioned issues increase thefabrication difficulty of the circuit substrate having componentsdisposed therein. In addition, since the thickness of a core layer isusually less than 100 microns (μm), which is also a great challenge fortoday's solder-resist fabrication.

SUMMARY OF THE DISCLOSURE

Accordingly, the disclosure is directed to a substrate structure havinga component-disposing area, which has simpler process and higherproduction yield rate.

The disclosure is also directed to a process for a substrate having acomponent-disposing area, which has simpler steps and higher productyield rate.

The disclosure provides a substrate structure having acomponent-disposing area, which includes a core layer, a firstdielectric layer, a laser-resistant metallic pattern and a seconddielectric layer. The core layer includes a first surface, a patternedmetallic layer and a component-disposing area, in which the patternedmetallic layer is disposed on the first surface and includes a pluralityof pads and the pads are located within the component-disposing area.The first dielectric layer is disposed on the core layer and includes aplurality of openings respectively exposing the pads. Thelaser-resistant metallic pattern is disposed on the first dielectriclayer and surrounds a projection area of the first dielectric layerwhich the component-disposing area is orthogonally projected on. Thesecond dielectric layer is disposed on the first dielectric layer andcovers the laser-resistant metallic pattern. The second dielectric layerincludes a component-disposing cavity corresponding to the projectionarea, penetrating through the second dielectric layer and communicatedwith the openings to expose the pads.

The disclosure provides a process for a substrate having acomponent-disposing area, and the process includes the following steps.Firstly, a core layer including a first surface, a metallic layer and acomponent-disposing area is provided. The metallic layer is disposed onthe first surface. Next, the metallic layer is patterned to form apatterned metallic layer, in which the patterned metallic layer includesa plurality of pads located in the component-disposing area. Then, afirst dielectric layer is formed on the first surface, in which thefirst dielectric layer covers the patterned metallic layer. Further, alaser-resistant metallic pattern is formed on the first dielectriclayer, in which the laser-resistant metallic pattern surrounds aprojection area of the first dielectric layer which thecomponent-disposing area is orthogonally projected on. After that, arelease film is disposed on the projection area of the first dielectriclayer, in which the release film covers a portion of the laser-resistantmetallic pattern within the projection area. Then, a second dielectriclayer is formed on the first dielectric layer, in which the seconddielectric layer covers the release film and the laser-resistantmetallic pattern. Further, a first open hole and a plurality of secondopen holes are formed, in which the first open hole surrounds theprojection area and penetrates through the second dielectric layer toextend to the laser-resistant metallic pattern, and the second openholes respectively penetrate through the second dielectric layer andextend to the pads; finally, making the release film separated from thefirst dielectric layer to form a component-disposing cavity.

In an embodiment of the disclosure, the component-disposing cavityexposes out the part of the laser-resistant metallic pattern surroundingthe projection area.

In an embodiment of the disclosure, the substrate structure having acomponent-disposing area further includes an electronic component,disposed in the component-disposing cavity and electrically connected tothe pads.

In an embodiment of the disclosure, the substrate structure having acomponent-disposing area further includes a plurality of bonding wires,electrically connected to the pads and the electronic componentrespectively.

In an embodiment of the disclosure, the substrate structure having acomponent-disposing area further includes a plurality of solder balls,electrically connected to the pads and the electronic componentrespectively.

In an embodiment of the disclosure, the material of the laser-resistantmetallic pattern includes copper, palladium, nickel and silver.

In an embodiment of the disclosure, the method of forming the first openhole and the second open holes includes laser drilling.

In an embodiment of the disclosure, the process for a substrate having acomponent-disposing area further includes disposing at least oneelectronic component in the component-disposing cavity, in which theelectronic component is electrically connected to the pads.

In an embodiment of the disclosure, the electronic component iselectrically connected to the pads by wire bonding or flip-chip bonding.

Based on the depiction above, in the disclosure, the dielectric layersare substituted for the solder mask layer disposed on the core layerwithin the component-disposing area in the prior art, so that, in thedisclosure, the dielectric layers located on the inside and the outsideof the component-disposing area can be integrally and simultaneouslyformed, which simplifies the conventional complicated substrate process.In addition, in the disclosure, a laser-resistant metallic pattern isdisposed on the dielectric layer for preventing the laser drilling frompenetrating through the dielectric layer, unlike the prior art where thelaser-resistant metallic pattern and the pads are together disposed onthe core layer so as to avoid the difficulty in the laser drilling depthcontrol. In short, the disclosure certainly simplifies the process for asubstrate having a component-disposing area and advances the productyield rate.

In order to make the features and advantages of the present disclosuremore comprehensible, the present disclosure is further described indetail in the following with reference to the embodiments and theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1H are cross-sectional diagrams showing a manufacturing processof a substrate having a component-disposing area according to anembodiment of the disclosure.

FIG. 2 is a cross-sectional diagram showing a manufacturing process of asubstrate having a component-disposing area according to anotherembodiment of the disclosure.

DESCRIPTION OF THE EMBODIMENTS

FIGS. 1A-1H are cross-sectional diagrams showing a manufacturing processof a substrate having a component-disposing area according to anembodiment of the disclosure. Referring to FIG. 1A, a manufacturingprocess of a substrate having a component-disposing area in theembodiment includes following steps. First, a core layer 110 shown byFIG. 1A including a first surface 112, a metallic layer 114 and acomponent-disposing area 116 is provided. The metallic layer 114 isdisposed on the first surface 112 and the component-disposing area 116is an area on the surface of the core layer 110 for disposing anelectronic component. It should be noted that, in the embodiment, thecore layer 110 is a bi-surfaces copper foil core layer, i.e., the twoopposite surfaces (the first surface 112 and a second surface 113opposite to each other) of the core layer 110 respectively have twocopper foils (the metallic layer 114 as shown by FIG. 1A), and circuitlayers are simultaneously fabricated on the two opposite surfaces of thecore layer 110 to improve the production efficiency. The followingprocess is against the first surface 112 of the core layer 110, and thedisclosure does not limit the structure on the second surface 113 of thecore layer 110 and the process thereof.

Next, referring to FIGS. 1A and 1B, a pattering process is performed onthe metallic layer 114 in FIG. 1A to form a patterned metallic layer 118as shown by FIG. 1B. The patterned metallic layer 118 includes aplurality of pads 118 a. The pads 118 a are within thecomponent-disposing area 116. Then, as shown by FIG. 1C, a firstdielectric layer 120 is formed on the first surface 112, in which thefirst dielectric layer 120 covers the patterned metallic layer 118 andthen a laser-resistant metallic pattern 130 is formed on the firstdielectric layer 120. The laser-resistant metallic pattern 130 surroundsa projection area 122 as shown by FIG. 1C, and a part of thelaser-resistant metallic pattern 130 is overlapped with the periphery ofthe projection area 122. The projection area 122 herein is an area whichthe component-disposing area 116 in FIG. 1B is orthogonally projected onthe first dielectric layer 120.

Referring to FIG. 1D, a release film 140 is disposed on the projectionarea 122 of the first dielectric layer 120 and covers the portion of thelaser-resistant metallic pattern 130 within the projection area 122.That is to say, the release film 140 covers the projection area 122 ofthe first dielectric layer 120, and covers the overlapped portion of thelaser-resistant metallic-pattern 130 and the periphery of the projectionarea 122. Referring to FIG. 1E, then, a second dielectric layer 150 isformed on the first dielectric layer 120, in which the second dielectriclayer 150 covers the release film 140 and the laser-resistant metallicpattern 130. Thereafter, the usual process of a circuit layer for acircuit substrate with multiple layers is repeatedly performed to formthe circuit layers stacked by each other on the second dielectric layer150 until the required layer number of the circuit layers is met.

Referring to FIG. 1F, a first open hole 162 and a plurality of secondopen holes 164 are formed. In more details, the first open hole 162surrounds the projection area 122, penetrates through the seconddielectric layer 150 and extends to the laser-resistant metallic pattern130. That is to say, the first open hole 162 takes the portion of thelaser-resistant metallic pattern 130 overlapped with the projection area122 as the profile thereof and penetrates from the outer surface 170 ofthe multiple circuit layers of the substrate structure to the seconddielectric layer 150, and then extends to the laser-resistant metallicpattern 130 under the second dielectric layer 150. In the embodiment,the method of forming the first open hole 162 and the second open holes164 includes laser drilling, and the material of the laser-resistantmetallic pattern 130 includes copper, palladium, nickel and silver.Since the laser is unable to penetrate copper, palladium, nickel andsilver, so that the laser-resistant metallic pattern 130 is able tocontrol the penetrating depth of the laser drilling. Thus, the firstopen hole 162 circling the above-mentioned profile on the projectionarea 122 and the first open hole 162 downward penetrates till thelaser-resistant metallic pattern 130 then stop. The second open holes164 respectively penetrate through the second dielectric layer 150 andextent to the pads 118 a. The material of the pads 118 a is the same asabove, copper, palladium, nickel and silver for controlling thepenetrating depth of the laser drilling.

Further, referring to FIGS. 1F and 1G, the release film 140 in FIG. 1Fis separated from the first dielectric layer 120 to form acomponent-disposing cavity 160 as shown by FIG. 1G for disposingelectronic components. In general, the material of the release film 140includes colloid with viscosity such as epoxy, polyethylene (PE) andpolypropylene (PP), which the disclosure is not limited to. The releasefilm 140 is usually a film able to be separated, and the film may bewithout viscosity or with slight viscosity after contacting a specificmaterial under a specific condition. In the embodiment. the release film140 is easy to be separated from the first dielectric layer 120, andafter the first open hole 162 circles the above-mentioned profile of theprojection area 122 and first open hole 162 downwards penetrates tillthe laser-resistant metallic pattern 130, the release film 140 isseparated from the first dielectric layer 120 to remove the circuitlayers on and above the release film 140 to form the above-mentionedcomponent-disposing cavity 160. At the time, the process for a substratehaving a component-disposing area in the embodiment is finished.

Then, as shown by FIG. 1H, an electronic component 180 of the embodimentis disposed in the component-disposing cavity 160 and electricallyconnected to the pads 118 a. In the embodiment, the electronic component180 can be, for example, a chip and electrically connected to the pads118 a by wire bonding so as to bury the electronic component 180 in thesubstrate, which the disclosure is not limited to. In other embodimentsof the disclosure, the electronic component 180 can be electricallyconnected to the pads 118 a by flip-chip bonding as well.

Following the above-mentioned process, a substrate structure 100 havinga component-disposing area as shown by FIG. 1H is fabricated andincludes a core layer 110, a first dielectric layer 120, alaser-resistant metallic pattern 130 and a second dielectric layer 150.The core layer 110 includes a first surface 112, a patterned metalliclayer 118 and a component-disposing area 116. The patterned metalliclayer 118 is disposed on the first surface 112 and includes a pluralityof pads 118 a. The pads 118 a are located within the component-disposingarea 116. The first dielectric layer 120 is disposed on the core layer110 and includes a plurality of openings 124 for respectively exposingthe pads 118 a. The laser-resistant metallic pattern 130 is disposed onthe first dielectric layer 120 and surrounds a projection area 122 asshown by FIG. 1C. A part of the laser-resistant metallic pattern 130 isoverlapped with the periphery of the projection area 122. It should benoted that the laser-resistant metallic pattern 130 and the pads 118 aare not located at the same layer of the substrate structure, instead,the pads 118 a are located on the core layer 110 while thelaser-resistant metallic pattern 130 is located on the first dielectriclayer 120 above the core layer 110.

The second dielectric layer 150 is disposed on the first dielectriclayer 120 and covers the laser-resistant metallic pattern 130. Thesecond dielectric layer 150 includes a component-disposing cavity 160corresponding to the projection area 122, penetrating through the seconddielectric layer 150 and communicated with the openings 124 to exposethe pads 118 a. In the embodiment, the substrate structure 100 having acomponent-disposing area can further include multiple circuit layersstacked with each other on the second dielectric layer 150, and thenumber of the circuit layers is depending on the actual demands ofproducts. The component-disposing cavity 160 penetrates through to thesecond dielectric layer 150 from the outer surface 170 of the circuitlayers and extends to the laser-resistant metallic pattern 130 below, soas to expose the portion of the laser-resistant metallic pattern 130surrounding the projection area 122.

In the embodiment, the substrate structure 100 having acomponent-disposing area can further have an electronic component 180and a plurality of bonding wires 190. The electronic component 180 isdisposed in the component-disposing cavity 160 and electricallyconnected to the pads 118 a. The bonding wires 190 are respectivelyconnected between the pads 118 a and the electronic component 180, sothat the electronic component 180 can be electrically connected to thepads 118 a via the bonding wires 190 and the electronic component 180can be buried in the substrate, which the disclosure is not limited to.

FIG. 2 is a cross-sectional diagram showing a manufacturing process of asubstrate having a component-disposing area according to anotherembodiment of the disclosure. Referring to FIG. 2, in the substratestructure 200 having a component-disposing area of the presentembodiment, a plurality of solder balls 290 are substituted for thebonding wires 190 to electrically connect the electronic component 280and the pads 218 a. At the time, the electronic component 280 disposedwithin the projection area 222 is electrically connected to the pads 218a through the solder balls 290 by flip-chip bonding.

In summary, in the disclosure, the dielectric layers are substituted forthe solder mask layer on the core layer within the component-disposingarea, so that the dielectric layers located on the inside and theoutside of the component-disposing area can be integrally andsimultaneously formed, which simplifies the conventional complicatedsubstrate process. In addition, in the disclosure, a laser-resistantmetallic pattern disposed on the dielectric layer is for preventing thelaser drilling from penetrating the dielectric layer, unlike the priorart where the laser-resistant metallic pattern and the pads are togetherdisposed on the core layer so as to avoid the difficulty in controllinglaser drilling depth. In short, the disclosure certainly simplifies themanufacturing process of a substrate having a component-disposing areaand improves the product yield rate.

It will be apparent to those skilled in the art that the descriptionsabove are several preferred embodiments of the disclosure only, whichdoes not limit the implementing range of the disclosure. Variousmodifications and variations can be made to the structure of thedisclosure without departing from the scope or spirit of the disclosure.The claim scope of the disclosure is defined by the claims hereinafter.

What is claimed is:
 1. A process for a substrate having acomponent-disposing area, comprising: providing a core layer, whichcomprises a first surface, a metallic layer and a component-disposingarea, wherein the metallic layer is disposed on the first surface;patterning the metallic layer to form a patterned metallic layer,wherein the patterned metallic layer comprises a plurality of padslocated in the component-disposing area; forming a first dielectriclayer on the first surface, wherein the first dielectric layer coversthe patterned metallic layer; forming a laser-resistant metallic patternon the first dielectric layer, wherein the laser-resistant metallicpattern surrounds a projection area of the first dielectric layer whichthe component-disposing area is orthogonally projected on; disposing arelease film on the projection area of the first dielectric layer,wherein the release film covers a portion of the laser-resistantmetallic pattern within the projection area; forming a second dielectriclayer on the first dielectric layer, wherein the second dielectric layercovers the release film and the laser-resistant metallic pattern;forming a first open hole and a plurality of second open holes, whereinthe first open hole surrounds the projection area and penetrates throughthe second dielectric layer and extends to the laser-resistant metallicpattern, and the second open holes respectively penetrate through thesecond dielectric layer and extend to the pads; and making the releasefilm separated from the first dielectric layer to form acomponent-disposing cavity.
 2. The process for a substrate having acomponent-disposing area as claimed in claim 1, wherein method offorming the first open hole and the second open holes comprises laserdrilling.
 3. The process for a substrate having a component-disposingarea as claimed in claim 1, further comprising: disposing at least oneelectronic component in the component-disposing cavity, wherein theelectronic component is electrically connected to the pads.
 4. Theprocess for a substrate having a component-disposing area as claimed inclaim 3, wherein the electronic component is electrically connected tothe pads by wire bonding or flip-chip bonding.